The present invention relates to a fluidic sensing device and more particularly to a fluidic device which will provide a differential pressure output proportional to the angle-of-attack of flow impinging on the sensing device.
Angle-of-attack sensors are widely used, particularly on aircrafts where an angle-of-attack system measures the angle between the longitudinal axis of the aircraft and the relative wind. In aircraft, the angle-of-attack is generally measured by a small, balanced vane on the side of the fuselage near the nose. The vane rotates freely to align itself to the relative wind. Attached to the vane is a synchro or other device which converts the vane angle into electrical signals that are transmitted to the cockpit or to an air data computer. Some vanes are equipped with damping means to prevent erratic output in turbulent air.
Another method of sensing angle-of-attack for aircraft is to use a small, forward-and-downward aiming vane which is pivotally mounted in the leading edge of the wing. The vane is spring centered and senses the particular angle at which the airflow at its location changes from over the wing to under the wing by pivoting upward or downward on its horizontal axis.
Vane type sensors, as well as other mechanical sensing devices, work very satisfactorily in air, that is, on aircraft for measuring angle of attack. These mechanical devices, however, have disadvantages, such as clogging, when used in liquids, particularly where debris is present.